Conventionally, for example, a constitution described in Patent Literature 1 has been known as a carbon dioxide gas recovery device. As shown in FIG. 8, a carbon dioxide gas recovery device 1000 includes an absorption tower 1001 that brings a carbon dioxide-containing gas containing carbon dioxide gas and a lean absorbent into contact with each other and causes the absorbent to absorb carbon dioxide gas in the carbon dioxide-containing gas to generate a rich absorbent, and a regeneration tower 1002 that regenerates the rich absorbent as a lean absorbent by heating the rich absorbent supplied from the absorption tower 1001 to separate carbon dioxide gas from the rich absorbent.
The regeneration tower 1002 includes a reboiler system 1003 that leads the lean absorbent from the regeneration tower 1002, heats the led lean absorbent, and reintroduces the resultant lean absorbent into the regeneration tower 1002, and a mixed gas cooling system 1004 that leads a mixed gas of carbon dioxide gas and a vapor fraction of a solute and a solvent (for example, water) of the absorbent from the regeneration tower 1002, cools the led mixed gas, condenses the vapor fraction of the solute and the solvent in the mixed gas, reintroduces the condensed vapor fraction into the regeneration tower 1002, and discharges a non-condensed carbon dioxide gas.
In the carbon dioxide gas recovery device 1000, the heat serving as a heat source for heating the rich absorbent in the regeneration tower 1002 is supplied through the absorbent heated by the reboiler system 1003 and reintroduced into the regeneration tower 1002. The reboiler system 1003 includes a reboiler body 1005 that heats the absorbent using externally-supplied heat as a heat source.